In organic chemistry, e.g. in biochemistry, as in a number of other fields, it is often necessary to subject to analysis very small quantitites of material. These materials are often the fruit of extensive preparatory processes which have been undertaken to isolate and identify a sample which is a minute fraction of the starting material. The amount of sample which is finally isolated is often beyond the control of the investigator. In any event, it is not rare for an investigator to have a sample prepared at great expense which is just a few microliters in volume. The storage and subsequent transfer of this material to an analytical instrument has heretofore involved excessive dilution or loss of a significant part of the sample in the vials, etc., in which it has been stored.
This problem of handling and preserving small samples has been taken into consideration in the design of analytical equipment. For example, sample injection valves and even pumps and analytical instruments have been designed to make the most efficient use of very small samples. Nevertheless, it has remained a problem for the preparative chemist to be able to supply the sample to the analyst in a way in which it may be efficiently transferred to the analytical apparatus. It has been a particular problem to achieve efficient transfer when the transfer operation is to be carried out on automatically actuated machinery.
It is these problems to which the Inventor has directed his efforts.